Who Is Frederica Wilson, the Cowboy-Hat-Wearing Florida Democrat Fighting Trump?

President Donald Trump's latest Twitter foe is a Democratic U.S. congresswoman from Florida who wears a glittering cowboy hat.

Trump on Wednesday accused Representative Frederica Wilson of lying about what the president told a widow of one of four U.S. soldiers killed in Niger earlier this month—and he said he can prove it.

"Democrat Congresswoman totally fabricated what I said to the wife of a soldier who died in action (and I have proof). Sad!" the president tweeted.

Wilson responded to the president's accusation Wednesday on CNN by stating she did not know what "kind of proof" Trump was talking about and called him a "sick man."

Their standoff started Tuesday, when Wilson claimed in an interview with CNN that she was in a car with the wife of U.S. Army Sergeant La David Johnson, Myeshia Johnson, and overheard the president say that the fallen trooper "knew what he signed up for…but when it happens, it hurts anyway." She said they were headed to Miami International Airport for the arrival of the soldier's remains.

"She has just lost her husband. She was just told that he cannot have an open casket funeral, which gives her all kinds of nightmares about what his body must look, what his face must look, and this is what the president of the United States says to her," Wilson told CNN.

Wilson, who represents Florida's 24th District, also said Myeshia Johnson believes the president didn't even know her husband's name, describing her as "distraught."

"When she actually hung up the phone and she looked at me and said, 'He didn't even know his name,'" Wilson said. "Now, that's the worst part."

Wilson was a longtime Florida state representative and senator before being elected to the U.S. House in 2011.

The controversy follows Trump telling reporters during a press conference Monday that his predecessors, specifically Barack Obama, did not place calls to military families who had lost loved ones in service. Trump later backtracked, saying he was "told" other presidents did not make such calls.

"President Obama, I think, probably did sometimes, and maybe sometimes he didn't," Trump said. "I don't know. That's what I was told. All I can do—all I can do is ask my generals," he said.

The president's comment sparked immediate backlash from former officials in the Obama and George W. Bush administrations, but Trump doubled down during an interview with Fox News Tuesday, suggesting Obama did not call White House Chief of Staff John Kelly after his son, Robert, died in Afghanistan in 2010.

It was later confirmed by a White House official that Obama did not call Kelly, but he did host him and his wife at a breakfast held for Gold Star families six months after Robert Kelly's death.